Hello, We are back again regarding our old JD 7520.
First off, does anyone know exactly how to determine the year of our 7520? we think its 1975 but would like to be sure
Anyway, I posted this issue last fall and after some discussion we began by simply replacing transmission filter and some fluid and the hydraulics came back. we assumed that fixed the issues. however last week upon lowering a piece of equipment to the field we lost clutch and steering again. not filter this time. I have located a TM 1053 so waiting on that. So far conversations with some John Deere mechanics around her we've had suggestions about relief valves, hydraulic compensator, supply line from rear to front hydraulic pump, charge pump etc. I did locate a TM 1053 so waiting for that. The top shaft below the cab is spinning so at this point we are trying to decide what to do to test or figure out if we have pressure/flow. Does anyone have experience working on the 1972-1975 JD 7520 hydraulic system when it comes to these things i mentioned, specifically the unit that the supply line is attached to which we are told houses relief valve(s)? its located just the the right of the transmission filter, picture off the internet is attached. i'm not the year of that machine and i am not at the tractor until later in the week but this pic is similar to what ours looks like. we're trying to figure out if we can simply disconnect that supply line and test for flow, or what issues we may deal with by doing so. hoping between the TM and some help here we will have some direction. any help would be very much appreciated.
First off, does anyone know exactly how to determine the year of our 7520? we think its 1975 but would like to be sure
Anyway, I posted this issue last fall and after some discussion we began by simply replacing transmission filter and some fluid and the hydraulics came back. we assumed that fixed the issues. however last week upon lowering a piece of equipment to the field we lost clutch and steering again. not filter this time. I have located a TM 1053 so waiting on that. So far conversations with some John Deere mechanics around her we've had suggestions about relief valves, hydraulic compensator, supply line from rear to front hydraulic pump, charge pump etc. I did locate a TM 1053 so waiting for that. The top shaft below the cab is spinning so at this point we are trying to decide what to do to test or figure out if we have pressure/flow. Does anyone have experience working on the 1972-1975 JD 7520 hydraulic system when it comes to these things i mentioned, specifically the unit that the supply line is attached to which we are told houses relief valve(s)? its located just the the right of the transmission filter, picture off the internet is attached. i'm not the year of that machine and i am not at the tractor until later in the week but this pic is similar to what ours looks like. we're trying to figure out if we can simply disconnect that supply line and test for flow, or what issues we may deal with by doing so. hoping between the TM and some help here we will have some direction. any help would be very much appreciated.
